LOUISVILLE, KY. (WDRB) -- Ultrasounds are pretty routine for pregnant women, but are they dangerous?

Neurologist Dr. Manuel Casanova has been researching a possible link between ultrasounds and autism at the University of Louisville for several years.  "Many people consider ultrasound taking a pretty picture," he says, "but really it's invasive sound waves that have effects on cells within the body....If not used properly it can be harmful."

Heartache over his own grandson's autism diagnosis drives him to get answers:  I told my daughter that I always had reservations about ultrasound and its connection to autism."

Casanova says in the early 90's, the FDA deregulated ultrasound, allowing seven to eight times more energy to be used in the scans.  It's partly because as people got heavier, more energy was needed to produce a quality picture.  He says since then, the number of ultrasounds per patient and the number of cases of autism have been climbing. 

He says, "I would say ultrasound, just like sound, is an energy wave and it deforms cells -- cells that are especially affected within the brain are the ones that provide for the formation of the cortex, so cortex is not formed correctly.  That's what we see in autism, that's what we see in ultrasound."

Casanova acknowledges ultrasound is a helpful screening technique, but warns it should be used in moderation for pregnancies that aren't high risk.  He says during a normal pregnancy, ultrasound should not be used at all, and no more than twice during the entire pregnancy.

"This is one bit of medical information gathering and imaging that hardly anyone puts up a fight against," Dr. Casanova says.  "These women are very excited and their families are very excited to see pictures of their babies."

Obstetrician Dr. Aaron Stewart says his typical non-risk patient has an average of 1½ ultrasounds per pregnancy.  And he doesn't believe there's a link to autism, saying, "There have been numerous studies about the safety of ultrasound going back 30 years, plus when it first came around, none of which have shown any direct link between autism or any other significant disorder at this point."

But Casanova says some women have as many as four ultrasounds during a normal pregnancy, and choose to do 3D or 4D scans that reveal more detail.  They're actually offered at many doctors' offices.  "Now we have keepsake images, 3D renderings," he says.  "We see color and images and why?  Because people want pretty pictures.  They're not informed about the dangers."

You don't even have to visit a doctor's office anymore to have an ultrasound.  After just a few minutes online, WDRB's Elizabeth Woolsey discovered dozens of ultrasound machines for sale on sites such as Amazon and eBay.

Dr. Casanova says, "Being able to buy your own ultrasound, bad idea.  There should be some type of regulation and certification in regards to usage.  I ask, how dangerous is it?  I would say it's very dangerous -- most of them do not even know what they're doing."

Casanova won't give up trying to fit together the pieces of the autism puzzle, searching for answers and sounding alarms about factors that could be linked to a diagnosis that causes so much suffering.

He says, "My life would be perfect if it wasn't because of the suffering this condition has caused us.  I suffer because my daughter suffers, because my grandson suffers.

Dr. Casanova points out that cultures that don't use ultrasound often, like the Amish, are at much lower risk of autism, and the diagnosis was fairly unknown in Somalia until people there immigrated to a developed country.  Then their rates of autism skyrocket.

Bottom line? He would like to see a lot more research on this issue.

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